Leaders of Scotland's main political parties take part in a TV debate for the first time with the main focus on independence. Voters in Scotland go to the polls in May for the third general election to the devolved Scottish Parliament since it was created in 1999. But some in Scotland, notably the Scottish Nationalist Party, want to go further to full independence. Britain's Prime Minister Tony Blair has warned Scottish voters of the economic risks of backing the nationalists in May's elections. Blair's Labour Party is trailing behind the Scottish Nationalists and faces losing control of the devolved parliament in what has traditionally been a stronghold of Labour support.